TWI817965B - A fastener, a fastening system, a punch, threaded fastener and a method of forming a threaded fastener - Google Patents

Abstract

The invention suggests a fastener system having a combination including a recess having a plurality of wings having an installation driving surface and a removal driving surface, and a wedge to present a tapered recess interface surface. The fastener system suggests a unique combination defining geometry of a recess including spiral, relative sizes, edges and surfaces, which can improve stability of engagement between the system components. A fastener, a punch and a method of forming a threaded fastener are also disclosed.

Description

Fasteners, fastener systems, punches, threaded fasteners, and methods of forming threaded fasteners

This application relates generally to drive systems for threaded fasteners, tools for their manufacture, and drivers for applying torque to such fasteners. More specifically, this application relates to fasteners constructed with straight wall grooves. Specifically, a fastener system is constructed in which the engagement of the driver and fastener has improved stability in terms of axial alignment and snap fit.

Threaded fasteners commonly used in industrial applications are often driven by power tools at high speeds and high torque loads. These conditions present difficult design considerations, especially with respect to drivetrains and more specifically with regard to threaded fasteners having a thread-engageable groove in the fastener head or a thread-engageable outer profile to the fastener head . Ideally, such a drive system would require easy manufacturing of the groove and head geometry, as well as the associated tools used to form the fastener head and the driver used to engage the groove or head geometry. The strength of the fastener head should not be adversely affected by the groove. Drivers should be matched to evenly distribute stress loads to avoid the creation of high localized stress areas that could cause deformation of the drive surface or driver, or both drive surface and driver, resulting in premature failure of the drive system.

When driving fasteners, the fastener system should prevent the driver from cam-out from the groove. In many applications, it is important that the fastener be able to withstand a number of cycles, such as those where the fastener must be removed to repair or replace parts or to remove and replace an access panel. Ideally, the fastener drive system should be able to perform these repeated cycles, especially in applications where the grooves can be coated and environments in which the grooves may become contaminated, painted or otherwise adversely affected by use. In these applications and environments, it is critical that the drive system maintains drive engagement and applies torque in a disengagement direction. There is a need to enable the drive system to apply even higher levels of torque when disassembling fasteners. This can also occur when fasteners are over-tightened during initial assembly or where corrosion occurs at the interface of the mating threads or when the assembly is heated. When cycles have placed increasing stress on the fastener. These and other features often face competing considerations and may have to be compromised among themselves.

Various groove and driver configurations are commonly used, including a large number of cross grooves, such as those described in U.S. Patent Re. 24,878 (Smith et al.), U.S. Patent 3,237,506 (Muenchinger), and U.S. Patent 2,474,994 (Tomalis) . Other fastener geometries include the multi-lobed geometry type described in US Patent 3,763,725 (Reiland) and the rib drive system described in US Patent 4,187,892 (Simmons). The "Allen" system is also in a common groove configuration, which is basically a straight-walled hexagonal socket that accepts a similarly shaped driver. Fastener systems including multiple lobes with helically configured transmission surfaces are described in U.S. Patent Nos. 5,957,645 (Stacy), 7,293,949 (Dilling), and 8,291,795 (Hughes), the entire contents of each of which are incorporated herein by reference. Each of these patents will be referred to herein as an example standard screw drive.

With the exception of ribbed systems, the walls and faces of the driver and groove are usually designed to fit closely together in an attempt to achieve face-to-face contact of the drive and driven surfaces. With cross-groove fasteners, this face-to-face engagement can only occur, if at all, when the driver is properly aligned and positioned within the groove. However, in reality, in order for the driver to be able to be inserted into the groove, there must be some gap between the two.

The necessity of this clearance is even more critical for grooves with substantially axially aligned (straight) drive walls, like the Reiland '725 patent and the Allen head system. In all such systems, the practical consequence of requiring this clearance is that it is difficult, if not impossible, to achieve a proper clearance between the driver and the groove surface. substantial face-to-face contact over a large area. With most drive systems for threaded fasteners, the driver mates with a groove in the head in a manner that results in point or line contact rather than large face-to-face contact. The actual contact area is usually substantially less than full face-to-face contact. Therefore, when torque is applied by the driver, the force exerted on the screw head tends to be concentrated in localized areas causing high localized stresses and unstable axial alignment. This high local stress can plastically deform the groove to form slopes or other deformations that lead to premature, unintended separation of the driver from the groove.

The Stacy '645 patent, co-owned with this application, describes a fastener system for maximizing the engageable surface area between the driver and drive surface. The disclosures of the '645 patent are incorporated by reference into this application. The grooves and drivers of the '645 patent are constructed with helically configured engagement surfaces aligned substantially parallel to the axis of the fastener and may generally be classified as a straight wall fastener system. A more robust embodiment of a helical drive fastener system is described in US Patent Nos. 7,891,274 (Dilling) and 8,291,795 (Hughes), which are jointly owned with this application. The disclosures of the Dilling '274 and Hughes '795 patents are also incorporated herein by reference.

The advantages of the invention described in the '645 patent are achieved by configuring the driving and driven surfaces of the driver and fastener, respectively, to be conformal to a segment of a spiral and, specifically, to a spiral configuration. The helical configuration is capable of retaining a substantially sufficient gap between the driver and the groove during insertion and removal of the driver, but allows for full seated rotation of the driver to fill the gap. The helical configuration of the drive wall of the driver and the driver engageable wall of the groove is such that when the helical walls engage, they engage over a relatively large area to thereby apply and distribute stress over the large area. The helically configured drive and driven walls are oriented to direct a substantial portion of the plus torque substantially perpendicular to the radius of the fastener with little, if any, reliance on frictional near-tangential engagement.

Another example of a straight wall fastener system is that described in US Patent 3,584,667 to Reiland. This reference is incorporated herein by reference. The Reiland '667 patent describes a fastener system in which the drive surface geometry consists of a series of semi-cylindrical surfaces configured essentially as a hexagonal shape. Reiland fastener systems generally refer to six blades and have a transmission surface parallel to the axis of the fastener.

Although straight wall fasteners are successfully and commonly used in many applications, they can experience difficulties caused by axial misalignment between the driver and the fastener. Additionally, it is difficult to obtain a reliable frictional engagement that provides a snap-fit feature. When initially installing a fastener, a snap-fit feature is desired to hold the fastener in alignment on the driver. This is particularly useful in high volume assembly line operations where power driver bits are used to apply torque to fasteners. When the fastener length is extended, axial alignment and snap fit are also important.

In many applications where straight wall drive systems are used, the driver may be powered or require insertion into a limited access location or by a robotic tool. In such situations, it is necessary to reliably engage the fastener to the driver prior to installation so that the driver can be used as an insertion tool as well as a driver. In these applications, a driver is inserted into the fastener to create a "snap fit." For a snap fit, the retention force between the driver and the fastener is sufficient to hold the fastener to the driver and to insert the fastener into the workpiece while the driver is moved into position. After the fastener is inserted into the workpiece, the force exerted on the fastener by the workpiece is sufficient to release the snap fit when the driver is removed. This "snap-fit" feature has been attempted in several different types of fasteners (e.g., in fastener/driver systems with a cross (cross-shaped geometry)), U.S. Patents 4,084,478 (Simmons) and 4,457,654 (Sygnator) ) showing several fastener/driver systems. A fastener system with a square transmission geometry is shown in US Patent 6,199,455 (Wagner). We have observed that the clamping fit focuses on the transmission surface.

U.S. Publication No. 2016/0305462 (Wunderlich) and U.S. Patent 8,955,417 (Stiebitz) show a six-blade groove with an inclined surface and a matching driver. exist In Wunderlich and Stiebitz, the inner radii of the groove leaves are separated by an inclined surface that matches a corresponding inclined surface in a special matching driver. We observed that the configuration did not reveal a snap-fit friction interface.

US 5,509,334 (Shinjo '334) and US Patent 5,435,680 (Schuster) show an additional six-blade groove with a sloped surface and a matching driver. In Shinjo '334 and Schuster, the inner radii of the groove leaves are separated by an inclined surface that matches a corresponding inclined surface in a special matching driver. We observe that these configurations teach tight engagement with one of the driver and grooves but do not reveal a snap fit as discussed above.

A similar but octagonal groove is shown in US Patent 5,219,253 (Shinjo '253). It also has a configuration that does not reveal a snap fit.

The "snap-fit" feature allows the fastener to releasably engage the driver to allow the driver and fastener to be manipulated as a unit in hard-to-reach, automated and other applications. The fasteners and screwdrivers can be detached using minimal force after they are installed.

The reference Larson (US Patent 4,269,246) is of interest because it uses a portion of a tapered driver to enhance the joint. In Larson, the inner radius of the driver slot is positioned parallel to the axis of the driver, while the top of the lobe tapers inward toward the tip. The express purpose of this is to avoid premature interference between the bit and the groove. We observed that the configuration resulted in circumferential and axial line contact between the driver and the groove and did not enhance stability or frictional engagement.

Reference Goss US Patent 5,461,952 is also of interest. In Goss, one of the rear side walls of the driver is tapered to provide a progressively thicker blade geometry that creates a frictional engagement on a drive surface. Since only one side wall is tapered, the engagement with the straight side transmission surface becomes a circumferential line contact. Again, only the driver head is reconfigured. This is because we were reluctant to change the groove geometry as this would result in a loss of compatibility with existing drivers. Retroactive compatibility with any improvements Fastening systems, specifically straight wall systems, are one of the design advantages.

Dilling US Patent 7,293,949, which is a common reference to this application, describes a fastener system configured to provide a snap fit in a straight wall fastener. In the Dilling '949 patent, interference surfaces are constructed on the interior non-drive transition surfaces between the wings of the fastener grooves. However, we have discovered that even more improvements with additional stability can be desired. Additional stability is used especially when fastener grooves are uneven. Non-uniformity can be attributed to many reasons. Examples include (but are not limited to) machine tolerances during manufacturing, uneven plating, uneven coating, painting or insertion after fastener insertion or deformation during previous installation or removal cycles.

It would be desirable to provide improvements to recessed head fasteners and drivers thereby reducing or eliminating these and other difficulties and improving stability.

Various embodiments described herein provide a fastener system with a straight-wall drive surface that provides a secure snap-fit feature while also improving the stability of the engagement between system components. One of the important features of the new system is that it allows existing standard straight wall screwdrivers to be joined in the new system. To achieve this goal, a new groove, a new groove and driver system, a new punch for forming a groove, and methods of using each are described below.

When initially installing a fastener, a snap-fit feature is desired to hold the fastener in alignment on the driver. This is particularly useful in high volume assembly line operations where power driver bits are used to apply torque to fasteners. When the fastener length is extended, axial alignment and snap fit are also important.

The straight wall fastener system of the present application is generally constructed with a groove having a plurality of wings extending radially outward from a central axis and a plurality of mating lobes that mate with the wings of the groove. son. Depending on the direction of the applied torque, each of the wings and blades has a transmission surface consisting of a mounting surface and a dismounting surface. These transmission surfaces are essentially constructed with the center of the fastener system The axes are in a parallel alignment relationship. Adjacent mounting and dismounting surfaces of the same wing or blade are separated at the outer radius by a non-drive wing outer end wall. The diameter formed by the outer radius will be referred to herein as the "A" dimension, as shown in the figure. Adjacent wings are separated at the inner radius by a non-drive transition profile. The diameter formed by the inner radius will be referred to herein as the "B" dimension, as shown in the figure.

To create an interference fit and provide a snap fit, a wedge formed in the transition profile to present a tapered interface surface is formed on the "B" dimension surface of the groove wing. The "B" dimension of the groove is narrowed relative to a standard straight wall groove to provide engagement with a standard straight wall driver. In another aspect, the "A" size has also been enlarged to provide additional compatibility with other standard straight wall screwdrivers. Those skilled in the art should understand that this article refers to a "standard" driver and recess involving generally accepted industry sizes in the relevant market. Reference will be made below to some specific examples of standard grooves and drivers. The grooves described provide traceability to allow the use of a standard driver in the grooves of this application.

In order to form the mating interface between the screwdriver and the fastener, the transition profile of the groove wing is tapered inward. The interface tapers radially inward from near the top of the groove to near the bottom of the groove.

The tapered interface surface provides stability to the driver to prevent improper alignment. When the groove and driver are improperly aligned, the mating can result in localized areas of high stress and more severe unstable axial alignment. These high local stresses can plastically deform the groove to form slopes or other deformations that lead to premature unintended separation of the driver from the groove and/or damage to the driver.

High localized stresses can be caused by factors such as the design of the grooves, inconsistencies in the manufacturing of fasteners or drivers, and difficulties faced by the field. Difficulties faced in the field may include, for example, misalignment of the driver and fastener or the inability to fully seat the driver in the groove due to paint or other debris that has collected in the groove. Even a slight misalignment between the driver and fastener or a change in the design specifications of the fastener or driver can result in a substantial reduction in the contact area between the driver and fastener, in many cases resulting in the loss of parts of the driver and fastener. Near point contact. imposed in such circumstances High torque will inevitably lead to concentrated stress in the material of the driver and groove, which in turn will lead to material failure through plastic deformation or cracking. Even slight plastic deformation of the groove and the engagement surfaces of the driver can adversely affect system performance. If the groove deforms to define a ramp-like surface that is inclined from the vertical, the driver will "spin out" of the groove under the influence of an applied load. This unscrewing is undesirable not only because it results in premature or uncontrolled detachment of the driver and groove, but also because a suddenly detached driver can slip onto the workpiece and damage the workpiece. Additionally, when driving a fastener, excessive stress in the driver blade can cause the blade to deform in a manner that reduces the surface area of contact with the fastener and effectively displaces the area of contact radially inward, thereby reducing the driver-groove The effectiveness of the joint and increases the risk of failure.

The disclosure of this application provides a fastener that includes a shank having a central longitudinal axis, a head at one end of the shank, the head having a groove centered on the axis, the groove being having a plurality of wings radiating outward from the axis, the groove having a groove outer radius defined by a radial distance from the axis to the outermost extent of the wings, each of the wings having a mounting a transmission surface and a disassembly transmission surface, the wing transmission surfaces being constructed to be aligned substantially parallel to the central longitudinal axis. In one aspect of the invention, a mounting transmission surface and a detachment transmission surface of adjacent wings are separated by a respective transition profile forming the radially innermost portion of the wings. In another aspect of the invention, a wedge is formed in the transition profile to present a tapered interface surface having a top, a bottom and a pair of opposing edges, the width of the interface surface being approximately The wider portion of the interface surface at the top of the groove tapers to a narrower portion of the interface surface near the bottom of the groove. And in yet another aspect of the invention, an interface surface is positioned at the base of the interface surface a root radial distance beyond a groove axis, the root radial distance defining the groove inner radius, the interface A surface is positioned at a top radial distance beyond the axis at the top of the interface surface, the top radial distance being greater than the bottom radial distance. And in another aspect of the invention, the groove inner radius and the groove outer radius are A ratio is from about 0.60 to about 0.65.

In another aspect, an interface surface is a non-drive surface. In another aspect, the interface surface is concave to have a radius of curvature equal to the radial distance from the axis to the interface surface. And in another aspect, the interface surface is concave to have a radius of curvature that is greater than the radial distance from the axis to the interface surface. In yet another aspect, an interface surface is concave and portions of the interface surface are positioned at a radial distance greater than or equal to the radial distance from the axis to the transition profile at the edges of the interface surfaces at. In a particular aspect, the groove is six-lobed. In another aspect, the interface surface tapers at an angle relative to the axis in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), and preferably about 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°).

In one aspect of the invention, the driving surfaces of the fastener head are configured to receive the driving surfaces of the fastener head end in a mating engagement. In another aspect, the tapered interface surface is configured to form a frictional engagement with the driver tip. And in another aspect, the groove interface surface is concave to have a radius of curvature greater than the radius of curvature of the lobes where the interface frictionally engages the lobes. And in yet another aspect, the tapered interface surface is configured to form a frictional engagement with the driver tip at the edge of the interface surface in the lower portion of the groove.

In one aspect of the invention, a tapered interface surface is formed between each pair of adjacent wings. In another aspect of the invention, a tapered interface surface is formed between a subset of all adjacent wing pairs. And in another aspect of the invention, there are a plurality of tapered interface surfaces symmetrically spaced around the groove.

The present invention further provides a fastener system including a fastener including a shank having a central shank longitudinal axis, a head located at one end of the shank, the head having a central shank axis centered on the shank axis. a groove having a plurality of grooves radiating outward from the axis of the handle wings having a groove outer radius defined by a radial distance from the shank axis to the outermost extent of the wings, each of the wings having an installation transmission surface and a detachment transmission surface, The wing transmission surfaces are constructed to be aligned substantially parallel to the longitudinal axis of the shank, the mounting transmission surfaces and the detachment transmission surfaces of adjacent wings being separated by a respective transition profile forming the radial end of the wings Internal part. In another aspect of the invention, a wedge is formed in the transition profile to present a tapered groove interface surface having a top, a bottom and a pair of opposing edges, the width of the interface surface being from The wider portion of the interface surface near a top of the groove tapers to a narrower portion of the interface surface near a bottom of the groove, and the interface surface is at the narrower portion of the interface surface. The base is positioned a radial distance beyond the axis of the shank, the radial distance defines the inner radius of the groove, and the interface surface is positioned at the top of the interface surface a radial distance beyond the axis of the shank. , the top radial distance is greater than the bottom radial distance. In another aspect of the invention, the system includes a driver having a driver tip having a central driver longitudinal axis, and the driver tip is configured to have a central portion and outwardly from the central portion A plurality of radiating lobes, each of which has a mounting transmission surface and a detachment transmission surface, the mounting and detachment transmission surfaces of adjacent lobes being separated by a transition profile forming the The radially innermost portion presents a sub-interface surface, and wherein the surfaces of the lobes are configured to be aligned parallel to the longitudinal axis of the driver. In another aspect of the invention, the groove is adapted to receive the driver tip, and the drive surfaces of the fastener head are configured to receive the drivers of the driver tip in a mating engagement. surface, and the groove and the driver interface surfaces are configured to form a frictional engagement when the fastener head and the driver head end are mated.

In a particular aspect of the fastener system of the invention, the ratio of the groove inner radius to the groove outer radius is from about 0.60 to about 0.65.

The present invention further provides a head end for forming a recessed head fastener. The punch. In one aspect of the invention, the punch includes: a body having a face configured to form and define the outer contour of the head; a tip integral with the body and extending from the face, the The tip has a central longitudinal axis, wherein the tip is configured to have a central portion and a plurality of wings radiating outwardly from the central portion, the tip having an outermost extent from the axis to the wings. The radial distance defines a tip outer radius, each of the wings having a surface configured to form a mounting transmission surface and a detachment transmission surface, the mounting transmission surface and the detachment transmission surface of the adjacent wing being formed by a respective transition profile separation, the profile forming the radially innermost portion of the wing, and wherein the transmission surfaces are configured to be aligned substantially parallel to the central longitudinal axis; and a wedge shape formed in the transition profile to Presenting a tapered interface surface, the interface surface has a top, a bottom and a pair of opposing edges, the width of the interface surface tapering from the wider part of the top of the interface surface close to a top of the tip to The base narrower portion of the interface surface near a base of the tip, the interface surface at the base of the interface surface is positioned a radial distance beyond the axis, the radial distance defining the recess The groove inner radius, the interface surface at the top of the interface surface is positioned a top radial distance beyond the axis, the top radial distance being greater than the bottom radial distance. In one aspect of the invention, the ratio of the groove inner radius to the groove outer radius is from about 0.60 to about 0.65.

The invention further provides a method of forming a threaded fastener having a thread-engageable groove formed at one end thereof, the method comprising using a punch to form the groove, the punch comprising: a body having a face configured to form and define the outer contour of the head; a prong integral with the body and extending from the face, the prong having a central longitudinal axis, wherein the prong is configured With a central portion and a plurality of wings radiating outwardly from the central portion, the tip having a tip outer radius defined by a radial distance from the axis to the outermost extent of the wings, the wings Each has a transmission surface configured to form an installation and a disassembly A surface of a transmission surface, the mounting transmission surface and the detachment transmission surface of adjacent wings being separated by a respective transition profile forming the radially innermost portion of the wing, and wherein the transmission surfaces are constructed to be substantially identical to The central longitudinal axis is aligned parallel; and a wedge is formed in the transition profile to present a tapered interface surface having a top, a bottom and a pair of opposed edges, the width of the interface surface being approximately The wider portion of the interface surface at the top of the tip tapers to the narrower portion of the interface surface near the bottom of the tip, the interface surface being at the bottom of the interface surface The interface surface is positioned at a top radial distance outside the axis, the root radial distance defining the groove inner radius, and the interface surface is located a top radial distance outside the axis, the top radial distance being positioned at the top of the interface surface. The radial distance is greater than the bottom radial distance. In another aspect of the method, the ratio of the groove inner radius to the groove outer radius is from about 0.60 to about 0.65.

The invention further provides a fastener having a head and a shank, the shank having a central longitudinal axis, wherein the head is configured to have a central portion and a plurality of wings radiating outwardly from the central portion, the Each of the wings has an installation transmission surface and a removal transmission surface separated by a non- transmission transition profile forming the radially innermost portion of the wing, and wherein the transmission surfaces are constructed to be substantially identical to The central longitudinal axis of the fastener is aligned parallel; and a wedge shape is formed in the non-drive transition profile of the fastener wings to present a tapered interface surface.

These and other features and advantages will be more clearly understood from the following detailed description and drawings of embodiments of the present application.

20: Fasteners

21: Top surface of head

22:Head

24: handle

25:end

40: Groove

41: Wing outer end wall

42:wing

43: Install transmission surface/transmission wall

44: Disassemble the transmission surface/transmission wall

45: Transition contour

46: Bottom

47:Top chamfered pyramid

48:Top

49: Bottom chamfer cone

50:Tapered interface surface/wedge

51:Top

52: Bottom

53: Edge

54: Cone angle

55: Edge

56: Groove inner radius/root (or bottom) radial distance

57: Groove outer radius

58: Width

59: Top radial distance

120:Fasteners

122:Head

126:Axis

140: Groove

141: Wing outer end wall

142:wing

143:Mounting surface

144:Disassembly surface

145: Groove transition profile

156: Groove inner radius

157: Groove outer radius

220:Screwdriver

226:Central longitudinal axis

241: Leaf outer end wall

242:leaf

243:Mounting surface

244:Disassembly surface

245: Driver transition profile

250:gap

256:Inner radius

302: Interface area

304:Interface area

310: Starter blade joint length/gap

402: Interface area

404: Interface area

410: Gap

420:Screwdriver

426:Central longitudinal axis

441: Leaf outer end wall

442:leaf

445: Transition contour

456:Inner radius

520:Punch

526:Central longitudinal axis

540: Tip/groove forming part

541: Wing outer end wall forming part

542: Wing forming part

543: Install the transmission surface forming part/wing transmission surface forming part/transmission wall forming part

544: Disassemble the transmission surface forming part/wing transmission surface forming part/transmission wall forming part

545: Transition contour forming part

546: Bottom forming part

547: Top chamfered pyramid forming part

548: Top forming part

549: Bottom chamfer pyramid forming part

550: Interface surface forming part

551: Top forming part

552: Bottom forming part

553: Edge forming part

554:Cone angle

555: Edge forming part

556: Root (or bottom) radial distance/inner radius of the groove forming part

557: Tip outer radius

558:Width

559: The top forms part of the radial distance

562: chamfer

564: chamfer

566:Depth

620:Fasteners

621:Screwdriver

640: Groove

641:Transition wing outer wall

642:Wing

643:Mounting surface

644:Disassembly surface

645: Transition contour

650:Tapered interface surface

720:Fasteners

721:Screwdriver

722: Fastener head

739: Driver socket

740:Protrusion

741:Transition wing outer wall

742:wing

743:Mounting surface

744:Disassembly surface

745: Transition contour

750:Tapered interface surface

812:Core

840: Spiral groove

842:wing

843: Install transmission surface

844: Disassemble the transmission surface

845: Transition contour

912:Core

940: High strength groove

941: Wing outer end wall

941a to 941d: Wing outer end wall

942:wing

942a to 942d: Wing

943: Install transmission surface

943a to 943d: Install transmission surface

944: Disassemble the transmission surface

944a to 944d: Removing the transmission surface

945: Transition contour

945a to 945d: Transition profile

1016B: Recessed fastener head

1026B: Remove wall/groove surface

1034B:Screwdriver

1044:Central axis

1044B: Screw axis

1044B':Screw axis

1048B:Removing the transmission wall

1054: starting point

1062:point

1068: Curved interface

1068': Driver-groove bending interface

1070: Counterclockwise torque

1072:Selected focus

1072':point

1074:Normal force

1076:weight

1076': weight

1078:weight

1078':Vector component

1080: Friction

1082: Tangent

1082': tangent

1084: weight

1084': Friction component

1086:weight

1086':Vector component

1120:Fasteners

1121:Screwdriver

1140: Groove

1142:wing

1150:Tapered interface surface

1220:Fasteners

1221:Screwdriver

1240:Protrusion

1242:wing

1250:Tapered interface surface

A: size

AH: size

AT: size

B: size

C: Gap

h: height

R ₁ :Total radius/wing tip radius

R ₂ : core radius

R ₂ ': core radius

w:width

α: angle

θ: rotation angle

Figure 1 is a perspective view of an example fastener groove in accordance with the disclosed embodiments.

Figure 2 is a top view of the groove of Figure 1.

FIG. 3 is a view taken along section line III-III of FIG. 2 .

Figure 4 is a top view of a standard groove.

FIG. 5 is a schematic diagram showing the groove profile of FIG. 2 overlapping with the groove profile of FIG. 4 .

Figure 6 is an enlarged view of part of Figure 5.

Figure 7 is a top view of a standard screwdriver paired with a standard recess.

FIG. 8 is a view taken along section line VIII-VIII of FIG. 7 .

Figure 9 is a top view of a standard driver paired with an example groove in accordance with the disclosed embodiments.

FIG. 10 is a view taken along the cross-sectional line X-X in FIG. 9 .

Figure 11 is a top view of a standard driver paired with an example groove in accordance with the disclosed embodiments.

Figure 12 is a view taken along cross-section line XII-XII of Figure 11.

Figure 13 is a perspective view of an example punch according to the disclosed embodiments.

Figure 14 is an end view of the punch of Figure 13.

Figure 15 is a side view of the punch of Figure 13.

Fig. 16 is a view taken along the cross-sectional line XVI-XVI of Fig. 14.

Figure 17 is a perspective view of an example fastener groove according to the disclosed embodiments.

Figure 18 is a perspective view of an example fastener protrusion in accordance with the disclosed embodiments.

Figure 19 is a cross-section of an example fastener groove according to the disclosed embodiments. Figure.

Figure 20 is a polar plot of a constant gap spiral in accordance with the disclosed embodiments.

21 is a force diagram illustrating the balance of forces between the driver and the groove in accordance with the disclosed embodiments.

Figure 22 is a force line diagram illustrating the force balance between a prior art driver and the groove.

Figure 23 is a perspective view of an example fastener protrusion in accordance with the disclosed embodiments.

Figure 24 is a plan view of the groove shown in Figure 23.

Figure 25 is a perspective view of an example fastener protrusion according to the disclosed embodiments.

Figure 26 is a plan view of the protrusion shown in Figure 25.

Related applications

This application claims priority to U.S. Patent Application No. 15/843,789 filed on December 15, 2017 and U.S. Patent Application No. 16/199,859 filed on November 26, 2018. The full texts of these applications are incorporated by reference. into this article.

Although the invention will be described with reference to the embodiments shown in the drawings, it will be understood that the invention may have alternative forms. Additionally, any suitable size, shape or type of components or materials may be used. Throughout this specification, the same reference numerals refer to similar features throughout the drawings.

Referring now to FIGS. 1-3 , a fastener recess according to an exemplary embodiment is shown. groove. Fastener 20 includes a shank 24 having a central longitudinal axis 26. A head 22 is positioned at one end 25 of the handle 24 . The head 22 has a six-lobed star-shaped groove 40 centered on the axis 26. Groove 40 has six wings 42 radiating outward from axis 26 . Groove 40 has a groove outer radius 57 defined by a radial distance from axis 26 to the outermost extent of the wing. Each of the wings 42 has an installation transmission surface 43 and a detachment transmission surface 44 (collectively referred to as transmission walls) separated by a wing outer end wall 41 . The wing drive surfaces 43, 44 are configured to be substantially parallel to the central longitudinal axis 26.

The mounting transmission surface 43 and the disassembly transmission surface 44 of adjacent wings 42 are separated by a respective transition profile 45 which forms the radially innermost part of the wing 42 . A wedge is formed in the transition profile to present a tapered interface surface 50 . Interface surface 50 is a non-transmission surface. Each interface surface 50 has a top 51 , a bottom 52 and a pair of opposing edges 53 , 55 . Each opposing edge 53, 55 results from a transition from the respective mounting and dismounting surface to the interface surface. The advantages of edges 53, 55 will be discussed below. The width 58 of the interface surface tapers from a wider point 51 of the interface surface, which is shown closer to the top 48 of the groove 40, to a narrower point 52 of the interface surface, which is shown closer to the bottom 46 of the groove 40. ).

The groove extends into the head 22 to reach a groove bottom 46 which may include a bottom inversion transitioning from the interface surface 50 and the bottom of the transmission walls 43, 44 and wing outer end wall 41 to the groove bottom 46. Pyramid 49. There is a top chamfer 47 transitioning from the top surface 21 of the head to the top 48 of the groove. However, alternative embodiments may not include top chamfer 47. It should be noted that in alternative embodiments, the top 51 and bottom 52 of the interface surface need not be close to the top 48 and bottom 46 of the groove 40 respectively. In these embodiments, the top 51 and bottom 52 of each interface surface may be offset from the top 48 and bottom 46 of the groove, respectively.

The interface surface 50 is positioned a radial distance 56 away from the axis 26 at a base 52 of the interface surface. The root radial distance defines the groove inner radius 56. Interface Surface 50 The top 51 of the interface surface is located a top radial distance 59 outside the axis 26. The top radial distance 59 is greater than the groove inner radius (root or bottom radial distance) 56 . The ratio of the groove inner radius 56 to the groove outer radius 57 is from about 0.60 to about 0.65. In another example, the ratio of the groove inner radius 56 to the groove outer radius 57 is from 0.60 to 0.65. The ratio of the groove inner radius 56 to the groove outer radius 57 is approximately 0.64 in one example and equals 0.64 in another example.

In one example, tapered interface surface 50 is concave relative to axis 26 . However, the tapered interface surface can also be flat. The tapered interface surface 50 may also have alternative shapes as long as edges 53, 55 are formed. In a particular concave configuration, tapered interface surface 50 has a radius of curvature equal to the radial distance from axis 26 to interface surface 50 . That is, the radius of curvature of the tapered interface surface 50 decreases from the top 51 of the interface 50 to the bottom 52 of the interface 50 . In an alternative embodiment, the radius of curvature of the concave tapered interface surface 50 is greater than the distance from the axis to the interface surface. In another alternative embodiment, portions of the concave interface surface are positioned at a radial distance greater than or equal to the radial distance from axis 26 to transition profile 45 at interface surface edges 53, 55.

Interface surface 50 is tapered relative to axis 26 at a taper angle 54 (FIG. 3) from about 0.5 degrees (0.5°) to about 12 degrees (12°). In a particular embodiment, taper angle 54 is preferably from about 4 degrees (4°) to about 8 degrees (8°) and more preferably about 6 degrees (6°).

FIGS. 1-3 illustrate the tapered interface surface 50 formed between each pair of adjacent wings 42 . However, in some applications it may be advantageous to construct interference profiles only between selected pairs (ie, a subset of transition profiles, based on the understanding that some misalignment often occurs). This can be avoided to some extent, for example in a multi-leaf configuration, by constructing the interference profile symmetrically around the grooves, such as between pairs of opposed wings, between diametrically opposed pairs of wings, every other The wings may be in a triangular configuration.

Figure 4 shows a standard six-blade threaded buckle with a prior art straight wall drive surface. An example of the file. An example standard six-lobed groove (also referred to as Torx® groove) is a fastener made in accordance with ISO 10664:2014 and NAS1800 (REV.4) and the full text of each of these standards is incorporated herein by reference. middle. Each size of a standard six-blade recess has a corresponding matching standard six-blade screwdriver. Another example of a standard six-blade recess and corresponding driver is described in the Hughes '795 patent. Each of these grooves will be collectively referred to herein as an example standard six-blade groove and their corresponding driver as an example standard six-blade driver.

The term "straight-wall drive face" may be used herein to refer to a fastener system in which the drive faces are substantially aligned (ie, parallel to the longitudinal axis of the fastener). In the fastener industry, statements such as "parallel alignment" are accepted with some tolerance for variation, and it should be understood that there are manufacturing tolerances for this alignment and may vary slightly in actual practice. Specifically, Figure 4 illustrates an example standard six-lobed groove, also described in the Hughes '795 patent (element 30 of Figure 2 thereof). Referring to Figure 4 of this application, a fastener system with a standard six-blade groove is constructed with a fastener 120 and a mating driver bit (not shown). Fastener 120 is configured to have a head 122 and a threaded shank (not shown). In this example, a six-lobed groove 140 is formed in the head 122 with the drive surface aligned parallel to the axis 126 of the fastener 120 (a straight wall). Groove 140 has a groove outer radius 157 defined by a radial distance from axis 126 to the outermost extent of wing 142 . The mounting and detachment surfaces 143 and 144 of adjacent wings are separated by transition profiles 145 and the mounting and detachment surfaces 143 and 144 of the same wing are each separated by a wing outer end wall 141 . The groove has an inner groove radius 156 defined by the radial distance from axis 126 to transition profile 145 . The ratio of the groove inner radius 156 to the groove outer radius 157 for a standard six-blade is between 0.70 and 0.75 (depending on the size of the driver) (see, for example, Shinjo '334, ISO 10664:2014 and NAS1800 (REV. 4) Standard), which is greater than the ratio of the groove inner radius 56 to the groove outer radius 57 of the groove 40 of the present application. As will be discussed below, the smaller ratio of the groove inner radius 56 to the groove outer radius 57 of the example groove 40 results in improved fit. There are many advantages to the torque of each blade of the screwdriver.

FIG. 5 is a schematic diagram showing the groove 40 profile of FIG. 2 (an example groove of the present application) overlaid with the groove 140 profile of FIG. 4 (a standard six-lobed groove). Figure 6 is an enlarged view of part of Figure 5. The outline of the groove 40 , specifically the outline of the bottom 52 of the interface surface 50 , is shown in dashed lines in FIGS. 5 and 6 , where the outline of the groove 40 overlaps the outline of the standard groove 140 . Although in this particular illustration, the geometry of the groove 140 is similar to the six-leaf fastener system of the Reiland reference cited above, it is intended only as a comparison of the present invention to a standard groove straight wall groove. One usage example. Of course, Figures 5 and 6 are not intended to indicate that both grooves can be used simultaneously, but merely illustrate the relative positions of the exemplary groove 40 and standard groove 140 features.

The interface surface 50 of the groove 40 extends (radially) closer to the axis 26 than the transition profile 145 of the groove 140 (the bottom 52 of the interface surface 50 is shown as a dashed line). Therefore, the inner radius 156 of the groove 140 (FIG. 4) is greater than the inner radius 56 of the groove 40 (FIG. 2). Additionally, the outer wing walls 41 of the groove 40 extend (radially) further away from the axis 26 than the transition wing outer walls 141 of the groove 140 . Therefore, the outer radius 157 of the groove 140 (FIG. 4) is smaller than the outer radius 57 of the groove 40 (FIG. 2). Each of these features (ie, smaller inner radius 56 and larger outer radius 57) results in an increased drive wall and provides an improved driver of drive torque per blade groove. This feature will be discussed below with reference to Figure 9.

FIG. 7 shows a top view of a standard six-blade screwdriver 220 paired with a standard six-blade recess 140 . The driver 220 has a driver tip, the cross-section of which is shown in the figure. The driver and the driver tip will together be referred to as driver 220. Driver 220 includes features that match those of standard recess 140, including, for example, a central longitudinal axis 226, a central portion, and a plurality of lobes 242 that radiate outward from the central portion that match recess wings 142. Each of the leaves 242 has a corresponding mounting surface 243 and a detachment surface 244. In addition, the driver 220 also includes a transition profile 245 positioned between adjacent lobes 242 and a lobe outer end wall 241 positioned between the mounting surface 243 and the removal surface 244 of the same lobe 242 . Each surface of the blade 242 is configured to align parallel to the driver longitudinal axis 226 .

As mentioned above and in fact, in order for the standard six-blade driver 220 to be inserted into the standard six-blade groove 140, there must be some gap 250 between the two. The gaps are spaced apart around the circumference of the driver 220.

FIG. 8 is a view taken along section line VIII-VIII of FIG. 7 . In addition to each of the standard six-blade driver 220 and the standard six-blade groove 140 having straight walls, each of the groove transition profile 145 and the driver transition profile 245 also has a straight wall, that is, each is parallel relative to the axis 126 (at within processing tolerance). Therefore, if the standard driver 220 is coaxial with the standard groove 140, the gap 250 remains constant and does not enhance the stability of the driver/recess engagement or the frictional engagement. Although the gap 250 allows the standard driver 220 to be easily inserted into the standard groove 140, the driver 220 is susceptible to accidental misalignment or wobbling in the groove 140 (axis 226 is not aligned with axis 126). Rocking causes concentrated forces on the screw heads in localized areas and results in high local stresses and unstable alignment. This localized high stress can plastically deform the groove to form ramps or other deformations that lead to premature and unintentional separation of the driver from the groove and cause unscrewing and driver/groove damage.

FIG. 9 shows the same standard six-blade driver 220 mated with an example groove 40. The example recess 40 is configured to receive in a mating engagement any driver made to correspond to the six-blade recess standard discussed above. As shown in FIG. 2 , groove 40 is configured to have a tapered interface surface 50 formed in the “B” dimension surface of groove transition profile 45 . As previously discussed, the inner radius 56 of the groove 40 (FIG. 2) is smaller than the inner radius 156 (FIG. 4) of a standard six-blade groove. This is a result of the tapered interface surface/wedge 50 tapering towards axis 26. Furthermore, the groove inner radius 56 is smaller than the top radial distance 59 .

The groove is narrowed relative to the standard six-blade groove 140 (FIG. 7) to provide a frictional engagement when the fastener 20 and driver 220 are mated together. The driver 220 has an inner radius greater than 56 and less than the groove inner radius 56 The inner radius 256 of the top radial distance 59 results in a negative gap, ie, interference at the interface regions 302, 304 discussed below. As shown in the figure, the "A" dimension is also enlarged relative to the standard six-blade recess 140 (Fig. 7) to allow for greater compatibility with other standard six-blade screwdrivers (such as the one described in the Hughes '795 patent). However, in an alternative embodiment, the "B" dimension is only narrowed relative to the standard groove size of one of the fastener types shown in Figure 4 and the "A" dimension is maintained, which would improve the standard six-blade screwdriver. It provides alignment stability but sacrifices additional compatibility.

Continuing with reference to Figures 9 and 10, the tapered interface surface 50 is configured to provide an effective frictional engagement ("snap fit") at edges 53, 55 resulting in two separated interface regions 302, 304. Because the opposing edges 53, 55 are located at the transition from the respective mounting and removal surfaces to the interface surface, less material must be deformed after insertion together to obtain a sufficient snap fit. The contact in the lower portion of the groove also provides a smaller contact area to also improve the snap fit. The two interface regions 302, 304 increase the contact stability between the groove 40 and the driver 220 by providing two points of stability at each interface surface 50 thereby improving axial alignment and reducing the risk of spin-out. Better stability is provided by having two interface areas rather than a single line or surface contact. A snap fit is created where the straight wall transition profile 245 contacts the tapered interface surface 50 . It should be noted that if there is sufficient contact at the interface areas 302, 304, some tilt in the driver walls may still provide an adequate snap fit. The improved snap fit of the example groove 40 will increase the speed at which the fastener is applied to the workpiece and reduce unscrewing and driver/groove damage. The degree of snap fit can be adjusted by adjusting the taper angle 54 during the production of the groove. Depending on the particular configuration of the standard six-blade screwdriver, each interface region 302, 304 may have various combinations of point and line contact along the edges 53, 55. Regardless of the type of contact, there are two interface regions 302, 304 between each tapered interface surface 50 and driver transition profile 245. The two interface regions 302, 304 provide increased stability to the mating joint of the driver head and the groove by helping to minimize vibration of the driver within the groove and are therefore larger than previously known grooves. Improved axial alignment and blade-to-wing engagement. This is especially true if the fastener 20 is uneven. Non-uniformity can be caused by many reasons. Examples include (but are not limited to) machine tolerances during manufacturing, uneven plating, uneven coating, painting or insertion after fastener insertion or deformation during previous installation or removal cycles. Example coatings include (but are not limited to) electro zinc + colorless, electro zinc + yellow, electro zinc + wax, mechanical zinc + colorless, mechanical zinc + yellow, black phosphate, black phosphate + oil, oil, wax, nickel , cadmium + wax, hot dip galvanizing, dacrotizing. It should be noted that in some instances (such as when the driver and fastener are not perfectly axially aligned or due to manufacturing tolerances in use), two interface areas may not be created in each groove wing. However, sufficient interface area can still be used in mating joints to achieve snap fit and stability benefits.

In addition to the enhanced stability provided by the frictional interface at interface regions 302, 304, the inner radius 56 of the groove 40 is smaller than the inner radius 156 of the standard six-lobed groove 140. The combination of the smaller inner radius 56 and the tapered interface surface 50 results in contact with the driver closer to the central axis 226. This provides an additional transmission wall for transferring torque, shown as the blade engagement length 310 . This results in a drive wall ratio of the starter blade engagement length 310 to the "AT" size, which ranges from about 0.15 to about 0.21. In a specific embodiment, the transmission wall ratio is preferably from about 0.17 to about 0.19 and more preferably about 0.18. 1. Increasing the transmission wall ratio increases the transmission torque from the screwdriver head to the groove of each blade. When used with a standard six-blade screwdriver, this increased drive wall ratio is an advantage over a standard six-blade recess utilizing a 0.11 drive wall ratio according to the six-blade recess standard.

Figure 10 is a view taken along section line X-X of Figure 9 through diametrically opposed interface region 302. It is shown that the frictional engagement between the driver tip end and the tapered interface surface 50 at the interface region 302 occurs in the lower portion of the groove. In an alternative embodiment, the tapered interface surface 50 at interface region 304 occurs in the lower third of the groove. A small gap 310 is provided between the driver 220 and the groove 40 after mating to ensure contact at the interface areas 302, 304 rather than at the bottom to allow The gap allows for plating buildup in the bottom of the groove and also prevents damage to the driver 220 tip.

11-12 illustrate another standard six-blade screwdriver 420 matingly engaged with the groove 40, namely, the six-blade screwdriver described in the Hughes '795 patent. Due to the improved configuration of groove 40, fastener 20 is capable of providing mating engagement with multiple six-blade screwdrivers, including the screwdriver of the Hughes '795 patent. Starter 420 includes a central longitudinal axis 426, a central portion, and a plurality of lobes 442 radiating outward from the central portion. Adjacent lobes 442 are separated by transition contours 445 . Compared to a standard six-blade screwdriver 220 and as described in the Hughes '795 patent, the "AH" dimension between the opposing blade outer end walls 441 of the blades 442 has been enlarged.

The driver 420 has an inner radius 456 that is greater than the groove inner radius 56 (FIG. 2) and less than the top radial distance 59 (FIGS. 2-3) to result in a negative gap, ie, interference at the interface regions 402, 404. The mating engagement of the driver 420 with the recess 40 provides advantages similar to those described with reference to Figures 9 and 10, including (but not limited to) reduced rocking and increased drive wall ratio which increases the driver head of each blade to the recess. groove transmission torque).

Figure 12 is a view taken along section line XII-XII of Figure 11 through diametrically opposed interface region 402. It is shown that the frictional engagement between the driver tip end and the tapered interface surface 50 at the interface region 402 occurs in the lower portion of the groove. In an alternative embodiment, the tapered interface surface 50 at the interface region 404 occurs in the lower third of the groove. For the same reasons discussed with reference to Figure 10, a small gap 410 is provided between the driver 420 and the groove 40 after mating.

The above characteristics and similar results can be applied to other straight wall fastener systems. As another example, the screw drive system of the referenced standard screwdriver patent may be modified by constructing a tapered interface surface/wedge on the opposing "B" dimension transition profile.

For example, Table 1 shows respective example "A" and "B" dimensions in inches for the outermost portion of the wing and the transition contour. These screwdrivers and corresponding grooves may be formed in accordance with SAE International Standard AS6305 (published in January 2017) and are available from The Phillips Screw Company ^TM under Drive Systems MORTORQ® Spiral. The full text of SAE International Standard AS6305 (published in January 2017) is incorporated by reference into this article.

The grooves of this application can be made in a conventional two-punch machine. The punch will typically be formed to include a body and a tip adapted to form the head of the fastener with corresponding grooves as disclosed (Figures 1-3 and 9-11). The punch may be formed according to conventional punch forming techniques, such as using a gear hobbing die. A driver according to the present invention may also be manufactured using known techniques, such as by stamping a driver shank using one or more forming dies to form the desired shaped wings or by milling the driver head using a specially shaped milling cutter.

Referring to Figures 13-16, the disclosed example grooves may be formed by a forging punch adapted to form the head of the fastener having the disclosed corresponding grooves. The grooves may be formed in, for example, a pair of punches using conventional forging techniques. 13-16 illustrate a punch 520 configured to form the disclosed example groove 40. The punch is a male mold corresponding to the female mold of the groove 40 embodiment described with reference to FIGS. 1 to 3 and 9 to 11 . Accordingly, features and dimensions described with reference to the disclosed punch 520 may also be applied to corresponding groove 40 features and embodiments, and vice versa.

The punch includes a body portion (not shown) having a side (not shown) and an integrated tip 540 protruding from the side. The tip 540 is complementary to the shape of the groove and the face of the punch is complementary to the shape of the face of the intended screw head (shown as a flat head in Figure 3). Tip 540 includes a top chamfered tapered portion 547 having a chamfer 564 . Tip 540 has a six-lobed star configuration centered on axis 526. Tip 540 has six wing-forming portions 542 radiating outward from axis 526 . Tip 540 has a tip outer radius 557 defined by a radial distance from axis 526 to the outermost extent of wing-forming portion 542 . Each of the wing forming portions 542 has an installation transmission surface forming portion 543 and a detachment transmission surface forming portion 544 (collectively referred to as transmission wall forming portions) separated by a wing outer end wall forming portion 541 . Wing outer end wall forming portion 541 has a depth 566 . The wing transmission surface forming portions 543, 544 are configured to be substantially parallel to the central longitudinal axis 526.

The mounting transmission surface forming portion 543 and the dismounting transmission surface forming portion 544 of adjacent wing forming portions 542 are separated by a respective transition profile forming portion 545 which forms the radially innermost portion of the wing forming portion 542 . A wedge-shaped portion is formed in the transition profile forming portion 545 to present a tapered interface surface forming portion 550 . Interface surface forming portion 550 forms a non-drive surface. An additional benefit of the location of the interface surface forming portion 550 is that the interface surface 50 is more easily formed by a punch in the "B" dimension than, for example, forming a groove in the "A" dimension (such as the grooves of the Hughes '795 patent). form. Having the interface surface formed in the "B" dimension has a lower risk that the material outside the wing will blow out during manufacturing.

Each interface surface forming part 550 has a top forming part 551, a bottom forming part 552 and a pair of opposing edge forming parts 553, 555. The advantages of edge forming portions 553, 555 have been discussed above with reference to opposing edges 53 and 55 of groove 40. Additionally, because edges 53 and 55 taper to a point near the bottom 46 of groove 40, punch 520 is able to remove more material through edge forming portions 553, 555 in this example and allow the groove to be formed. Program is higher effect. The width 558 of the interface surface forming portion 550 tapers from the wider portion of the top forming portion 551 of the interface surface (which is shown proximate the top forming portion 548 of the groove 540) to the wider portion of the bottom forming portion 552 of the interface surface forming portion 550. Narrow (shown as close to the bottom forming portion 546 of the groove 540).

Tip 540 extends to a groove bottom forming portion 546 which may include a transition from the bottom forming portion of interface surface forming portion 550 and drive wall forming portions 543, 544 and wing outer end wall forming portion 541 to groove bottom forming portion 546 A bottom chamfered cone forming part 549. The bottom chamfered taper forming portion has a chamfer 562 . There is a top chamfer forming portion 547 transitioning from the body portion to a top forming portion 548 of the groove. However, alternative embodiments may not include top chamfer forming portion 547. It should be noted that in alternative embodiments, the top- and bottom-forming portions 551 , 552 of the interface surface-forming portion need not be proximate to the top- and bottom-forming portions 548 , 546 , respectively, of the groove-forming portion 540 . In such embodiments, the top-forming portion 551 and the bottom-forming portion 552 of each interface surface-forming portion may be offset from the top-forming portion 548 and the bottom-forming portion 546 of the groove-forming portion, respectively.

The interface surface forming portion 550 is positioned a base (or base) radial distance 556 away from the axis 526 at the base forming portion 552 of the interface surface forming portion 550 . The root radial distance 556 defines the groove forming portion inner radius 556 . The interface surface forming portion 550 is positioned a top forming portion radial distance 559 away from the axis 526 at the top forming portion 551 of the interface surface forming portion 550 . The top forming portion radial distance 559 is greater than the groove forming portion inner radius (root or bottom radial distance) 556. The ratio of the groove forming portion inner radius 556 to the tip outer radius 557 is from about 0.60 to about 0.65. The ratio of the groove-forming portion inner radius 556 to the tip outer radius 557 is about 0.64 in one example, while in another example the ratio is equal to 0.64.

The tapered interface surface forming portion 550 is concave relative to the axis 526 . However, The tapered interface surface forming portion 550 may also be flat. If edge forming portions 553, 555 are formed, tapered interface surface forming portion 550 may also have an alternative shape. In a particular concave configuration, tapered interface surface forming portion 550 has a radius of curvature equal to the radial distance from axis 526 to interface surface forming portion 550 . That is, the radius of curvature of the tapered interface surface forming portion 550 decreases from the top forming portion 551 of the interface forming portion 550 to the bottom forming portion 552 of the interface forming portion 550 . In an alternative embodiment, the radius of curvature of the concave tapered interface surface forming portion 550 is constant and equal to the top forming portion radial distance 559. In another alternative embodiment, portions of concave interface surface forming portion 550 are positioned in a radial direction that is greater than or equal to the radial distance from axis 526 to transition profile forming portion 545 at interface surface edge forming portions 553, 555 distance.

Interface surface forming portion 550 is tapered at an angle relative to axis 26 from about 0.5 degrees (0.5°) to about 12 degrees (12°). In a particular embodiment, the interface surface forming portion 550 preferably follows a taper angle 554 from about 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°) (Fig. 16) Taper.

13-16 illustrate tapered interface surface forming portions 550 formed between each pair of adjacent wing forming portions 542. However, in some applications it may be advantageous to construct interference profiles only between selected pairs (ie, a subset of transition profiles, based on the understanding that some misalignment often occurs). This can be avoided to some extent, for example in a multi-leaf configuration, by constructing the interference profile symmetrically around the grooves, such as between pairs of opposed wings, between diametrically opposed pairs of wings, every other The wings may be in a triangular configuration.

Form a threaded fastener with a driver-engageable groove, like groove 40 (Figs. 1-3), that is, by mechanically forming the head and groove to match the corresponding standard six-blade screwdriver discussed above. Matching grooves. The head 22 may be formed in a conventional two-punch machine in which the buckle is made. The end of a piece of metal or other material is supported on a die of a punch machine and its head end is first struck by a punch that partially forms the head and then is finished by a finish that processes the head and forms a groove into which the driver can engage. The machining punch (such as the punch described with reference to Figures 12 to 15) impacts. The general manufacture of fasteners is well known and will not be further described in this application. One of these well-known methods may be used to construct the present invention.

Figures 17-26 each illustrate various screw drive fastener systems (such as the screw drive fasteners and drivers discussed in the Stacy '645 and Dilling '274 patents and modified to include the tapered interface surface/wedge shape discussed above) Various embodiments of a tapered interface surface/wedge implemented in . Each of these is discussed in more detail below.

Referring to Figure 17, a portion of a fastener 620 and a driver 621 is shown according to an example embodiment. For the sake of clarity, the remaining parts of the fastener 620 and the driver 621 are omitted. The fastener 620 includes a groove 640 and a plurality of wings 642 . Each wing 642 includes a mounting surface 643 and a detachment surface 644 in a spiral configuration, each separated by a transition wing outer wall 641 . Driver 621 is configured to have a helically configured drive surface that mates with a corresponding surface of fastener groove 640 while establishing a snap fit discussed above. Similar to prior art helical configuration fasteners, the overall shape and number of wings may differ from the illustrated example. The general shapes of the groove 640 and the driver 621 are similar except that the wings of the driver 621 are smaller than the corresponding wings 642 of the groove 640 to provide a gap between the driver and the fastener to facilitate the engagement and disassembly of the driver 621 with the groove 640 . Additionally, the bit mounting and removal walls are slightly different from the corresponding groove walls, so rotation of the bit will provide a complete face-to-face engagement on both the mounting and mounting walls. As indicated above, the driver/fastener interface surface is configured in the general shape of a segment of a spiral on both the mounting surface and the removal surface.

A transition profile 645 extends between the mounting and detachment surfaces of adjacent wings. A wedge is formed in transition profile 645 to present a tapered interface surface 650 . Tapered interface Surface 650 is configured in the same manner and allows groove 640 to have the advantages of tapered interface surface 50 (FIG. 1) discussed above.

Figure 18 shows a fastener 620 and driver similar to that of Figure 17, except that in the example embodiment of Figure 18, the "groove" is located in the driver (which will be referred to herein as a socket or driver socket 739). The combination of 621 includes a fastener 720 and a screwdriver 721. Figure 17 shows a groove 640 in the fastener 620 and a driver 621 designed as a "male" inserted into the "female" of the groove 640. In the embodiment of Figure 18, the situation is reversed. Fastener 720 of FIG. 18 includes a protrusion 740 configured to extend axially outwardly from fastener head 722 for engagement with a sub-socket 739. Similar to groove 640 (FIG. 17), protrusion 740 includes a plurality of wings 742. Each wing 742 includes a mounting surface 743 and a detachment surface 744 in a spiral configuration, each separated by a transition wing outer wall 741 . A transition profile 745 extends between the mounting and detachment surfaces of adjacent wings. A wedge is formed in transition profile 745 to present a tapered interface surface 750 . The tapered interface surface 750 is configured in the same manner and allows the protrusion 740 to have the advantages of the tapered interface surface 50 discussed above. It should be noted that the tapered interface surface 750 is shown not extending along the full height of the protrusion 740 . As mentioned previously with respect to the tapered interface surface 50 (FIG. 1), the tapered interface surface may be offset from the top and/or bottom of the groove/protrusion, respectively.

Driver socket 739 is configured with a mating drive surface for engaging the drive surface of protrusion 740 and for establishing an interface area with tapered interface surface 750, as discussed above with respect to tapered interface surface 50 (FIG. 1).

Two example helical configurations are shown in Figure 19: a helical groove 840 (dashed line) (such as the embodiment described in the Stacy '645 patent); and a high strength helical groove 940 (such as the Dilling '274 patent) The embodiment described in and the embodiment of Figure 17). The configurations described with reference to FIG. 19 may also be applied to the embodiments of FIGS. 17 and 18 and other embodiments disclosed herein. The configurations shown in Figure 19 can also be applied to a fastener groove, protrusion or other Each screwdriver, as it should be understood that only a small gap between the fastener and the screwdriver is provided for insertion and removal of the screwdriver. It should be noted that in accordance with the present invention, the groove is configured with the disclosed interface surface/wedge, for example, such that the driver tip has a groove root radial distance at the transition profile that is greater than the groove root radial distance of the modified groove and less than the top diameter of the modified groove. a radius to the distance (one-half the driver "B" size). For simplicity, tapered interface surfaces (eg, 650, 750 corresponding to fasteners 620 and 720) are not shown in Figure 19.

The helical groove 840 is shown in phantom with wings 842 extending outwardly from a core 812 having a radius (R ₂ ') and bounded by a mounting drive surface 843 and a detachment drive surface 844 . As will be discussed further below, with reference to Figure 20, at least one of the side walls (eg, drive surfaces 843, 844) defines a segment of a bolt.

Figure 20 illustrates the polar coordinates of an ideal spiral having the desired properties for use in a spiral configuration as it can be oriented relative to an axis of rotation corresponding to the longitudinal axis of a threaded fastener and will remain so rotated through an angle θ Parallel to and spaced from the non-rotating helix. As shown in Figure 20, when rotated through an angle θ to the position indicated at B, the ideal spiral indicated at location A will remain parallel to the spiral at location A but will be spaced from the spiral at location A by one of the distance indicated at C. gap. Although the size of gap C will increase with increasing rotation angle θ, for any given angle θ, gap C will remain constant throughout the length of the helix. The geometry of a constant gap spiral is defined by the following equation expressed in polar coordinates:

where: θ = angle of rotation (in radians) of a ray intersecting the curve at a distance r from the axis of rotation; R _i = starting radius measured from the axis of rotation to the starting point of the spiral; and R =Helix radius at a rotation angle θ also measured from the rotation axis.

It will be understood from the above that when a driver is formed from drive walls embodying a constant gap spiral and is driven to engage the helical walls of a groove, the helical drive walls on the driver will fully and simultaneously engage the corresponding helical drive walls on the groove. The polar diagram of Figure 20 is only intended to depict an ideal spiral in which the gap between the rotational positions of the spiral is constant (i.e., a constant gap spiral) such that the spirals can be considered parallel.

According to the invention, the helical surface(s) of the transmission wall of one wing of the groove are positioned such that the starting point 1054 of the helix is radially spaced apart from the central axis 1044 of the groove by a radius _Ri . According to the present invention, the portion of the helical surface positioned closer to the starting point 1054 will transmit a greater portion of the applied torque in a direction that will rotatably drive the screw than the portions positioned more outwardly. The helical drive surfaces and driver-engageable grooves will transmit torque most efficiently by configuring the surfaces to be conformal to the portion of the helix that is more closely positioned at the starting point 1054. According to the present invention, the force transmission wall should be curved to extend from R=1 on Figure 20 to no more than about R=3.5 (indicated at point 1062) and preferably at R=1 The part of the spiral extending within the range of about R = 2 is conformal. With respect to the angle of the arc subtended by the desired inner portion of the spiral, the angle may be up to about 125°, more preferably about 90° or less, and most preferably about 45° or less.

Figures 21 and 22 are force diagrams showing force components acting at any point along a curved surface of a joint driver and groove wall. Figure 21 illustrates a force diagram of the present invention. Figure 21 shows a starter 1034B having a detachment drive wall 1048B engaged face-to-face along a curved interface 1068 with a detachment wall 1026B of a recessed fastener head 1016B. Figure 21 diagrammatically represents the force vector when a counterclockwise torque (shown at 1070) is applied about the axis 1044B of the screw. At a selected point of interest 1072, the driver 1034B applies a force 1074 in a direction perpendicular to the interface 1068. Grooved face 1026B. The normal force 1074 is decomposed into a component 1076 that exerts only torque on the screw and another component 1078 that creates radially outward compressive stress but no torque. Additionally, the normal force 1074 results in a friction force 1080 directed along a tangent 1082 of the interface 1068 . The frictional force 1080 is then decomposed into a component 1084 that is additive to the torsional component 1076 and another component 1086 that is opposite and subtractive from the radially outward component 1078 . The magnitude of the friction force 1080 relative to the normal force 1074 depends on the friction coefficient, which will, of course, vary with surface smoothness, lubricity and the material of the screw. For example, the friction coefficient may range from about 0.1 to about 0.4, where a friction coefficient of 0.4 has been selected in the force development diagrams of FIGS. 21 and 22 . Thus, Figure 21 illustrates that the geometry of the driving and driven walls according to the present invention generates torque primarily from the normal force component 1074, even with a high coefficient of friction assumed for the purposes of the illustration. The torque transmission capability of a fastener embodying the present invention is largely independent of the vector component 1084 of friction.

Figure 22 is a force diagram similar to that of Figure 21 but depicting the effect of a driver-groove curved interface 1068' oriented such that the curved interface at a point 1072' Tangent 1082' at 1068' will be oriented more nearly perpendicular to a radius drawn from screw axis 1044B' to point 1072'. This configuration has characteristics of the configuration described in Bradshaw US Patent No. 2,248,695. It should be apparent from a comparison of Figures 22 and 21 that the prior art configuration results in a substantially higher radially outward load on the screw head (as indicated by the difference in length between vector components 1078' and 1086') and is primarily dependent on A variable and often unpredictable friction phenomenon used to produce torque. In the prior art, the dependence on friction was shown by comparing the relative proportions of friction component 1084' and component 1076'. It will be understood from the above that a line perpendicular to the tangent of the helical segment will form an angle α with the radius from the longitudinal axis to the tangent point, which represents the extent to which the force exerted by the driver will be transmitted to the fastener as torque. In the embodiments disclosed herein, the angle α should not be less than 17° and preferably, be substantially greater than 17°. The main purpose of the present invention is to provide high torque available The drive system from which the screw is transmitted to the fastener reduces the risk of buckling or cracking of the screw head and its significant dependence on friction characteristics.

Referring back to Figure 19, there is shown a helical groove 840 and a high strength groove 940 in which the wings 842, 942 contain helical drive walls in both the installation and disassembly directions but where one of the drive walls in each wing has a larger diameter than the other. One is the large torque capacity. Grooves 840, 940 provide greater torque capability in the disassembly direction because the disassembly transmission wall has a larger arc length and corresponding area than the installation transmission wall. Because the force is exerted on a larger surface area in the direction of disassembly, a larger torque can be applied in this direction.

Although the present invention is most efficiently practiced using the constant gap helices described above, a system may be provided that incorporates a slightly different helix than the optimal substantially constant gap helix while still providing significant advantages over prior art. Figure 19 illustrates examples of such grooves 840, 940. For example, the groove is shown with four wings 842, 942, each having a detachment drive surface 844, 944 and a mounting drive surface 843, 943 configured to have a constant clearance helix, And the mounting transmission surfaces 843, 943 have different helical configurations oriented so that a major portion of the force is directed from the driver toward the groove in a torque-generating direction. In one example, the transition profile 845 of the mounting and removal surfaces on each of the driver and groove wings may be formed as an arcuate profile.

Regarding high strength groove 940, we observed that the cross-sectional shape of high strength groove 940 is configured to have a core radius ( _R2 ) greater than that of helical groove 840 ( _R2 '). The overall radius R ₁ remains constant, whereby the height h of the wings 942 needs to be shortened to accommodate the enlarged core radius R ₂ . This results in a reduction in the surface area of the transmission surface where poor performance is expected. The cross-section of wing 942 is further modified by moving the mounting transmission surface 943 and the removal transmission surface 944 outward in a parallel manner to form a truncated wing shape with an outer wing end wall 941 . Wing outer end wall 941 is configured to be segmentally conformal to a circle, concentric with core 912, and have a diameter that is greater than the diameter of the core. Drive surfaces 943 and 944 are configured to intersect the core diameter in transition profile 945 between adjacent wings, such as wings 942a and 942d having transition profile 945d. The transition profile 945 has a concave form conforming to the diameter of the core.

Wings 942a, 942b, 942c, and 942d are respectively defined by installation transmission surfaces 943a, 943b, 943c, 943d, wing outer end walls 941a, 941b, 941c, 941d, and detachment transmission surfaces 944a, 944b, 944c, 944d. Adjacent wings intersect the core circumference 912 at transition contours 945a, 945b, 945c, 945d.

These changes have not resulted in poor performance, but have resulted in an unexpected increase in driver strength and a significant improvement in the seat torque capabilities of the screw drive fastener system. The reduction in transmission surface area is compensated by improving the distribution characteristics from the transmission surface to the core.

The increased strength and increased seat torque of the high strength groove 940 and corresponding driver can be attributed to the groove and driver configuration having an increased core diameter compared to prior art screw fastener systems. It is logical to attempt to maintain the transmission surface area by configuring the transition surface as a convex extension similar to the mounting transmission surface 943 and removal transmission surface 944 of prior art designs. Conversely, drive surfaces 943 and 944 are configured to intersect the core diameter in a transition profile 945 between wings 942 that has a concave form that conforms to the core diameter. This increases core strength but further shortens the wing section and reduces the transmission surface area. Additionally, by shortening the outer tip of the wing section and moving the drive surface outwards in parallel with prior art configurations, the wing can be enlarged and formed with a blunt tip, further increasing the strength of the system. We observed that the center of mass of the wing will also move outward thereby achieving an improved load distribution.

This is accomplished by shortening the cross-section wings of both the groove and the driver to extend radially beyond the core diameter. The wing cross section of the driver/groove is further modified by moving the mounting and removal surfaces in a parallel manner to form a truncated wing shape with a blunt tip. The blunt tip is constructed to Conformal to a circle, concentric with the core, and having a diameter greater than the diameter of the core.

To this end, the cross-section of the wing portion of the high strength groove 940 (and therefore the wing portion of the corresponding driver) is cut outward from the core circumference 912 and inward from the wing outer end wall 941 . In this manner, wings 942 are configured such that the ratio of core radius R ₂ to wing tip radius R ₁ is greater than 0.55 and the transition profile 945 between wings 942 is a concave segment of the core circumference. Preferably, the ratio of R ₂ /R ₁ is in the range of 0.65 to 0.70. Additionally, the width w of wing 942 is expanded while maintaining the profile of the drive surface consistent with prior art fastener systems. The ratio h/w of the height h of the wing section to its width w is configured to be approximately equal to or less than 0.5. In comparison, for example with reference to groove 840 of Figure 19, the ratio _R2 '/ _R1 can be calculated to be approximately 0.46 and the ratio (h'/w') of helical groove 840 can be calculated to be approximately 0.93. These modified dimensions have proven to provide a significantly beneficial increase in the strength of the driver bit to the groove 940 .

Figure 23 shows an example of a helical groove 1140 in a head of the fastener 1120 and a corresponding six-winged screwdriver 1121. Groove 1140 has similar characteristics to grooves 640 (FIG. 17) and 940 (FIG. 19), including a plurality of tapered interface surfaces 1150 between adjacent wings 1142. In contrast to the four-wing embodiments of grooves 640 and 940 , groove 1140 includes six wings 1142 . Figure 24 is a plan view of groove 1140 looking down along a longitudinal axis of fastener 1120 (Figure 23).

FIG. 25 shows an example of a spiral-shaped protrusion 1240 protruding from a head of the fastener 1220 and a corresponding six-winged screwdriver 1221 . Protrusion 1240 has characteristics similar to protrusion 740 (FIG. 18) and groove 940 (FIG. 19), including a plurality of tapered interface surfaces 1250 between adjacent wings 1242. The protrusion 1240 includes six wings 1242 compared to the four-wing embodiment of the protrusion 740 . Figure 26 is a plan view of protrusion 1240 looking down along a longitudinal axis of fastener 1220 (Figure 25).

The above description and drawings are considered merely illustrative of specific embodiments that achieve the features and advantages described herein. Modifications and substitutions may be made for specific conditions, materials, and others. Fasteners are constructed in many different configurations and the application of the subject matter of this application is not intended to be limited to any particular type. type. For example, the groove 40 in the embodiment of FIGS. 1 to 3 is in a six-lobed shape. However, the principles of the invention may be applied to groove systems having three, four, five, eight or other numbers of wings and lobes. As another example, the above-described embodiment illustrates a common form of fastener system involving a female groove on the fastener and a male-configured driver. However, the interference profile of the fastener system of the present invention can also be applied to the reverse configuration with a female groove (socket) on the driver and a male profile fastener, as shown in the specific embodiment above. As another example, some fasteners do not have heads that clamp the workpiece to the base plate. Instead, it can use a second threaded section to engage the workpiece. Given that certain fasteners have clamping heads, the advantages provided by the illustrated configuration may be obtained in other fastener types such as non-clamping fasteners and others. Accordingly, the present invention is not to be considered limited to the above description and drawings, but is intended to cover all such alternatives, modifications, substitutions and variations.

20: Fasteners

21: Top surface of head

22:Head

25:end

40: Groove

42:wing

46: Bottom

47:Top chamfered pyramid

48:Top

50:Tapered interface surface/wedge

51:Top

52: Bottom

53: Edge

55: Edge

Claims (79)

A fastener comprising: a. a handle having a central longitudinal axis; b. a head located at one end of the handle; c. the head having a groove centered on the central longitudinal axis ;d. The groove has a plurality of wings radiating outward from the central longitudinal axis, and the groove has a groove outer radius defined by a radial distance from the central longitudinal axis to the outermost extent of the wings. ; e. Each of the wings has a mounting transmission surface and a detachment transmission surface, which transmission surfaces are constructed to be substantially parallel to the central longitudinal axis; f. The mounting transmission surface of the adjacent wing and the The disassembly transmission surfaces are separated by a respective transition profile forming the radially innermost portion of the wings; g. a wedge shape formed in the transition profile to present a tapered interface surface having a top , a bottom and a pair of opposing edges, the width of the interface surface tapering from the wider part of the top of the interface surface close to a top of the groove to the width of the interface surface close to a bottom of the groove The bottom is narrow; h. The interface surface is located at a radial distance outside the central longitudinal axis at the bottom of the interface surface. The root radial distance defines an inner radius of the groove. The interface surface is located at the bottom of the interface surface. The top of the interface surface is located at a top radial distance beyond the central longitudinal axis, the top radial distance is greater than the bottom radial distance; and at least one of the installation transmission surface and the disassembly transmission surface of the fasteners , configured to define a spiral having a starting point spaced a starting radius from the central longitudinal axis of the fastener, and extending to an outer terminal end with a radius not exceeding approximately 3.5 times the starting radius point. Such as the fastener of claim 1, wherein the interface surface is a non-transmission surface. The fastener of claim 1, wherein the interface surface is concave to have a radius of curvature equal to a radial distance from the central longitudinal axis to the root interface surface. The fastener of claim 1, wherein the interface surface is concave to have a radius of curvature greater than a radial distance from the central longitudinal axis to the root interface surface. The fastener of claim 1, wherein the interface surface is concave and portions of the interface surface are positioned a radial distance from the central longitudinal axis that is greater than or equal to a diameter from the central longitudinal axis to the transition profile direction distance. The fastener of claim 1, wherein the groove has exactly six or four of the wings. The fastener of claim 1, wherein the interface surface tapers at an angle relative to the central longitudinal axis, the angle being in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), and preferably In the range of about 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°). The fastener of claim 1, wherein the driving surfaces of the fastener head are configured to receive the driving surfaces of the head end of the fastener in a mating engagement manner. The fastener of claim 8, wherein the tapered interface surface is configured to form a A frictional joint. The fastener of claim 8, wherein the tapered interface surface is configured to form a frictional engagement with the driver tip at an edge of the interface surface in the lower portion of the groove. The fastener of claim 1, wherein a tapered interface surface is formed between each pair of adjacent wings. The fastener of claim 1, wherein a tapered interface surface is formed between a subset of all adjacent wing pairs. The fastener of claim 12, wherein there are a plurality of tapered interface surfaces spaced symmetrically around the groove. The fastener of claim 1, wherein any part of the helical segment does not have a tangent, and a vertical line of the tangent forms an angle of less than 17° with a radius from the central longitudinal axis to the tangent point. The fastener of claim 1, wherein the spiral includes a constant gap spiral. For example, the fastener of claim 15, wherein the spiral is defined by the following equation:

where: θ = angle of rotation (in radians) of a ray intersecting a curve at a distance r from an axis of rotation; R _i = the starting point measured from the axis of rotation to the starting point of the spiral initial radius; and R = the radius of the spiral at a rotation angle θ also measured from the rotation axis. The fastener of claim 14, wherein the spiral segment defined by at least one of the mounting transmission surface and the disassembly transmission surface of the fastener extends from the starting point to a distance approximately three times the starting radius. An outer terminal point at a radius. The fastener of claim 1, wherein the spiral is circumscribed by at least one of the mounting transmission surface and the disassembly transmission surface of the fastener with an arc not greater than approximately 125°. The fastener of claim 1, wherein the cross-sectional shape of each wing includes a wing width and a wing height, and the ratio of the wing height to the wing width is equal to or less than 0.5. The fastener of claim 19, wherein the groove includes a central core and a wing tip, the central core has a first radius, the wing tip has a second radius, and wherein the first radius and the second The ratio of radii is greater than 0.55. The fastener of claim 20, wherein the wing outer end wall has a radius equal to the second radius. The fastener system of claim 1, wherein the ratio of the groove inner radius to the groove outer radius is from about 0.60 to about 0.65. A fastener system comprising: a. a fastener having: i. a handle having a central longitudinal axis of the handle; ii. a head located at one end of the handle; iii. the head having A groove centered on the handle axis; iv. The groove has a plurality of wings radiating outward from the handle axis, and the groove has a radial direction from the handle axis to the outermost range of the wings. The outer radius of the groove is defined by a distance; v. Each of the wings has an installation transmission surface and a detachment transmission surface, and the wing transmission surfaces are constructed to be substantially parallel to the longitudinal axis of the handle; vi. The installation transmission surface and the disassembly transmission surface of adjacent wings are separated by a respective transition profile forming the radially innermost portion of the wings; vii. a wedge shape formed in the transition profile to present a taper The groove interface surface has a top, a bottom and a pair of opposing edges. The width of the interface surface tapers from the wider part of the interface surface close to one of the tops of the groove to close to The interface surface at the narrower point of the interface surface at the bottom of the groove; and viii. The interface surface at the bottom of the interface surface is positioned a radial distance beyond the axis of the shank (the "bottom"), the The root radial distance defines the groove inner radius, and the interface surface is positioned at a top radial distance beyond the shank axis at the top of the interface surface, the top radial distance being greater than the bottom radial distance; ix where the At least one of the installation transmission surface and the removal transmission surface of the fastener is configured to define a spiral having a starting point spaced a starting radius from the central longitudinal axis of the fastener, and the spiral extends to a radius of An outer terminal point that exceeds approximately 3.5 times the starting radius; b. A driver having a driver head having a central driver longitudinal axis, wherein the driver head is configured to have a central portion and a plurality of lobes radiating outward from the central portion, the lobes having Each has a mounting transmission surface and a detachment transmission surface, the mounting and detachment transmission surfaces of adjacent lobes being separated by a transition profile forming the radially innermost portion of the lobes and presenting a common sub-interface surface, and wherein the surfaces of the lobes are constructed to be aligned parallel to the longitudinal axis of the driver; c. wherein the groove is adapted to receive the driver head end, and the drive surfaces of the fastener head are constructed to The drive surfaces of the driver tip are received in a mating engagement, and the grooves and driver interface surfaces are configured to form a frictional engagement when the fastener head and the driver tip are mated. The fastener system of claim 23, wherein the ratio of the groove inner radius to the groove outer radius is from about 0.60 to about 0.65. For example, the fastener system of claim 23, wherein the interface surfaces are non-transmission surfaces. The fastener system of claim 22, wherein the groove interface surface is concave to have a radius of curvature equal to the radial distance from the axis to the groove interface surface. The fastener system of claim 23, wherein the groove interface surface is concave to have a radius of curvature greater than the radial distance from the axis to the groove interface surface. The fastener system of claim 23, wherein the groove interface surface is concave, and the interface surface Each portion is positioned at a radial distance greater than or equal to the radial distance from the axis to the transition profile at the edge of the groove interface surface. The fastener system of claim 23, wherein the groove and the driver are in the shape of six leaves. The fastener system of claim 23, wherein the groove interface surface tapers at an angle in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), and preferably about 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°). The fastener system of claim 23, wherein the tapered interface surfaces are configured to form a frictional engagement with the driver tip at edges of the interface surfaces. The fastener system of claim 23, wherein the tapered interface surface is configured to form a frictional engagement with the driver tip at an edge of the interface surface in the lower portion of the groove. The fastener system of claim 23, wherein the driver head end has a radius at the transition profile that is greater than the radial distance of the groove root and less than the radial distance of the groove top. The fastener system of claim 23, wherein any part of the helical segment does not have a tangent, and a vertical line of the tangent forms an angle of less than 17° with a radius from the longitudinal axis to the tangent point. The fastener system of claim 23, wherein the spiral includes a constant gap spiral. For example, the fastener system of claim 35, wherein the spiral is defined by the following equation:

where: θ = rotation angle (in radians) of a ray that intersects the curve at a distance r from the rotation axis; R _i = the starting point measured from the rotation axis to the starting point of the spiral initial radius; and R = the radius of the spiral at a rotation angle θ also measured from the rotation axis. The fastener system of claim 34, wherein the helical segment defined by at least one of the fastener installation transmission surface and the disassembly transmission surface extends from the starting point to a position approximately three times the starting radius an outer terminal point at a radius. The fastener system of claim 23, wherein an arc of the spiral circumscribed by at least one of the fastener installation transmission surface and the disassembly transmission surface is not greater than approximately 125°. The fastener system of claim 23, wherein the cross-sectional shape of each groove wing includes a width and a height, and the ratio of the wing height to the wing width is equal to or less than 0.5. The fastener system of claim 27, wherein the groove includes a central core having a first radius and a tip having a second radius, and wherein a ratio of the first radius to the second radius is greater than 0.55. The fastener system of claim 40, wherein the wing outer end wall has a radius equal to the second radius. A punch for forming the head end of a recessed head fastener, which includes: a body having a face configured to form and define the outer contour of the head; a tip that is in contact with the body Integrated with and extending from the face, the tip has a central longitudinal axis, wherein the tip is configured to have a central portion and a plurality of wing-forming portions radiating outwardly from the central portion, the tip having a central longitudinal axis extending from the axis A radial distance to the outermost extent of the wing-forming portions defines a tip outer radius, each of the wing-forming portions having a mounting transmission surface forming portion and a detachment transmission surface forming portion. a surface on which the mounting transmission surface forming portion and the dismounting transmission surface forming portion of adjacent wing forming portions are separated by a respective transition profile forming portion forming the radially innermost portion of the wing forming portion, and wherein the drive surface forming portions are configured to be aligned substantially parallel to the central longitudinal axis; and a wedge forming portion is formed in the transition profile forming portion to present a tapered interface surface forming portion, the interface surface forming portion The portion has a top-forming portion, a bottom-forming portion and a pair of opposed edge-forming portions, the interface surface-forming portion having a width ranging from the top-forming portion to the interface surface-forming portion adjacent to a top-forming portion of the tip. The wider portion tapers to the narrower portion of the base-forming portion of the interface surface-forming portion proximate a base of the tip; the interface surface-forming portion is positioned outside the axis at the base of the interface surface-forming portion a root (bottom) radial distance defining an inner radius of the groove-forming portion, the interface surface-forming portion being positioned a top radial distance outside the axis at the top of the interface surface-forming portion, the top radial distance is greater than the bottom radial distance; wherein at least one of the mounting drive surface forming portions and the dismounting drive surface forming portions is configured to define a spiral having a spaced apart relationship with the central longitudinal axis a starting point of the starting radius, and the spiral extends to an outer terminal point with a radius not exceeding approximately 3.5 times the starting radius. The punch of claim 42, wherein the tip is configured such that the formed interface surface is a non-drive surface. The punch of claim 42, wherein the tip is configured such that the formed interface surface is concave to have a radius of curvature equal to the radial distance from the axis to the interface surface. The punch of claim 42, wherein the tip is configured such that the formed interface surface is concave to have a radius of curvature greater than the radial distance from the axis to the interface surface. The punch of claim 42, wherein the tip is configured such that the resulting interface surface is concave, and portions of the interface surface are positioned greater than or equal to the transition from the axis to the edges of the interface surfaces at one of the radial distances of the contour. The punch of claim 42, wherein the tip is configured such that the formed groove is six-lobed. The punch of claim 42, wherein the tip is configured such that the resulting interface surface tapers at an angle in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), And preferably in the range of about 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°). The punch of claim 42, wherein the prong is configured such that the driving surfaces of the fastener head are configured to receive the driving surfaces of the fastener head end in a mating engagement. The punch of claim 49, wherein the tip is configured such that the formed tapered interface surface is configured to form a frictional engagement with the driver tip end. The punch of claim 49, wherein the tip is configured such that the tapered interface surface is configured to form a frictional engagement with the driver tip at an edge of the interface surface in the lower portion of the groove. A method of forming a threaded fastener having a thread-engageable groove formed at one end thereof, the method comprising: forming the groove using a punch, the punch comprising: a body, It has a face configured to form and define the outer contour of the head; a prong integrated with the body and extending from the face, the prong having a central longitudinal axis, wherein the prong is configured to have a A central portion and a plurality of wings radiating outward from the central portion, the tip having a tip outer radius defined by a radial distance from the axis to the outermost extent of the wings, each of the wings Having a surface configured to form a mounting transmission surface and a detachment transmission surface of adjacent wings separated by a respective transition profile forming the radially innermost portion of the wing , and wherein the transmission surfaces are constructed to be aligned substantially parallel to the central longitudinal axis; and a wedge shape is formed in the transition profile to present a tapered interface surface having a top, a bottom and A pair of opposing edges, the width of the interface surface tapering from the wider part of the top of the interface surface close to a top of the tip to the wider part of the bottom of the interface surface close to a bottom of the tip narrow; the interface surface is positioned at a radial distance outside the axis at the bottom of the interface surface, the root radial distance defines the groove inner radius, and the interface surface is positioned at the top of the interface surface At a top radial distance outside the axis, the top radial distance is greater than the bottom radial distance; wherein at least one of the installation transmission surface forming portions and the disassembly transmission surface forming portion is configured to define a spiral, the spiral There is a starting point spaced a starting radius from the central longitudinal axis, and the spiral extends to an outer terminal point with a radius not exceeding about 3.5 times the starting radius. The method of claim 52, wherein the formed interface surface is a non-transmission surface. The method of claim 52, wherein the formed interface surface is concave to have a radius of curvature equal to the radial distance from the axis to the interface surface. The method of claim 52, wherein the formed interface surface is concave to have a radius of curvature greater than the radial distance from the axis to the interface surface. The method of claim 52, wherein the formed interface surface is concave and portions of the interface surface are positioned at one of the radial distances greater than or equal to the transition profile from the axis to the edges of the interface surfaces. radial distance. The method of claim 52, wherein the groove is formed to have exactly six or four of the wings. The method of claim 52, wherein the formed interface surface tapers at an angle in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), and preferably about 4 degrees ( 4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°). The method of claim 52, wherein the driving surfaces of the fastener head are configured to receive the driving surfaces of the fastener head end in a mating engagement. The method of claim 59, wherein the tapered interface surface is configured to form a frictional engagement with the driver tip. The method of claim 59, wherein the tapered interface surface is configured to form a frictional engagement with the driver tip at edges of the interface surfaces in the lower portion of the groove. A fastener including: a head and a shank, the shank having a central longitudinal axis, wherein the head is configured to include a groove having a central portion and a plurality of wings radiating outward from the central portion , each of the wings has an installation transmission surface and a detachment transmission surface separated by a non- transmission transition profile forming the radially innermost portion of the wing, and wherein the transmission surfaces are constructed to substantially aligned parallel to the central longitudinal axis of the fastener; and a wedge shape formed in the non-drive transition profile of the fastener wings to present a tapered interface surface, wherein the groove is configured to interface with a Corresponding screwdriver head ends are paired and joined, so that the screwdriver head end has a radius at a transition profile that is greater than the radial distance of the inner root of a groove and less than the radial distance of the top of a groove, wherein the mounting transmission surfaces form part and disassembly at least one of the transmission surface forming portions is configured to define a spiral having a starting point spaced a starting radius from the central longitudinal axis, and The spiral extends to an outer terminal point with a radius not exceeding approximately 3.5 times the starting radius. The fastener of claim 62, wherein the ratio of the inner radius of the groove root to the outer radius of the groove is from about 0.60 to about 0.65. The fastener of claim 63, wherein the driving surfaces of the fastener head are configured to receive the driving surfaces of the head end of the fastener in a mating engagement. The fastener of claim 62, wherein the drive surfaces of the fastener head are configured to receive the drive surfaces of a driver head in a mating engagement and the tapered interface surface is configured to form a driver head with A frictional joint. The fastener of claim 62, wherein the drive surfaces of the fastener head are constructed in a groove extending into the fastener head and the groove is adapted to receive the drive surfaces of the head end of the fastener. A fastener system comprising: a. a fastener having: i. a handle having a central longitudinal axis of the handle; ii. a head located at one end of the handle; iii. the head having A groove centered on the handle axis; iv. The groove has a plurality of wings radiating outward from the handle axis, and the groove has a radial direction from the handle axis to the outermost range of the wings. The outer radius of the groove is defined by a distance; v. Each of the wings has an installation transmission surface and a disassembly transmission surface. The transmission surfaces of the wings The surfaces are constructed to be aligned substantially parallel to the longitudinal axis of the shank; vi. The mounting transmission surface and the detachment transmission surface of adjacent wings are separated by a respective transition profile forming the radially innermost portion of the wings ; vii. A wedge shape formed in the transition profile to present a tapered groove interface surface having a top, a bottom and a pair of opposing edges, the width of the interface surface being close to that of the groove The wider portion of the top of the interface surface at the top of the groove tapers to the narrower portion of the interface surface near the bottom of the groove; and viii. The interface surface is positioned at the bottom of the interface surface The interface surface is located at a top radial distance outside the shank axis, the root radial distance defining the groove inner radius, and the interface surface is positioned at a top radial distance outside the shank axis, the top radial distance a radial distance greater than the base radial distance, wherein at least one of the fastener mounting drive surfaces and the detachment drive surfaces is configured to define a spiral having a starting radius spaced from the longitudinal axis of the fastener starting point and extending to an outer terminal point at a radius not greater than about 3.5 times the starting radius; b. A driver having a driver head end, the driver having a central driver longitudinal axis, wherein the driver head The end is configured to have a central portion and a plurality of lobes radiating outwardly from the central portion, the driver tip having a dimension in a driver diameter extending from an end of a lobe located on an opposite side of the driver tip, the driver tip being Each of the leaves has a mounting transmission surface and a detachment transmission surface, the mounting and detachment transmission surfaces of adjacent lobes being separated by a transition profile forming the radially innermost portion of the leaves and presenting a sub-interface surface, and wherein the surfaces of the blades are configured to be aligned parallel to the longitudinal axis of the driver; c. wherein the groove receives the driver head end, and the drive surfaces of the fastener head can be aligned along the driver blades The engagement length accepts the transmission surfaces of the bit end of the screwdriver in a mating engagement manner, and the The groove interface surface and the driver interface surface are configured to form a frictional engagement such that when the fastener head and the driver head end are mated and engaged, a region of interference is formed between the groove interface surface and the driver interface surface; d. The ratio of the driver blade engagement length 310 to the driver diameter is from about 0.15 to about 0.21. The fastener system of claim 67, wherein the groove has a groove outer radial distance defined from the central longitudinal axis to the outermost extent of the wings, and the groove inner radius is relative to the groove The ratio of outer radii ranges from about 0.60 to about 0.65. The fastener system of claim 67, wherein the tapered interface surfaces form a frictional engagement with the driver tip. For example, the fastener system of claim 67, wherein the tapered interface surfaces are non-transmission surfaces. The fastener system of claim 67, wherein the tapered interface surfaces are symmetrically spaced around the groove. The fastener system of claim 67, wherein the interface surface has a top, a bottom and a pair of opposing edges, the width of the interface surface starting from a wider portion of the top of the interface surface near a top of the groove tapering to a narrower portion of the interface surface near a bottom of the groove; the interface surface is positioned at a root radial distance from the axis at the bottom of the interface surface, the root diameter a radial distance defining the inner radius of the groove, the interface surface at the top of the interface surface being positioned a top radial distance beyond the axis, the top radial distance being greater than the bottom Radial distance. The fastener system of claim 67, wherein the formed interface surface is concave and portions of the interface surface are positioned greater than or equal to the radial distance from the axis to the transition profile at the edges of the interface surfaces a radial distance. The fastener system of claim 67, wherein the groove has exactly six or four of the wings. The fastener system of claim 67, wherein the interface surface tapers at an angle relative to the axis, the angle being in the range of about 0.5 degrees (0.5°) to about 12 degrees (12°), and preferably at about In the range of 4 degrees (4°) to about 8 degrees (8°), and more preferably about 6 degrees (6°). A driver for driving a fastener, including: a female driver defining a central longitudinal axis and a groove centered on the central longitudinal axis and adapted to receive a male configured fastener, the groove including : A plurality of wings radiating outward from the central longitudinal axis; each of the wings having a mounting transmission surface and a detachment transmission surface constructed to be substantially aligned with the central longitudinal axis Parallel alignment; the mounting transmission surface and the disassembly transmission surface of adjacent wings are separated by a respective transition profile forming the radially innermost portion of the wings; a wedge shape formed in the transition profile to present A tapered interface surface having a top, a bottom and a pair of opposing edges, a width of the interface surface Tapering from a wider portion at the top of the interface surface near a top of the groove to a narrower portion at the bottom of the interface surface near a bottom of the groove; and the interface surface at The base of the interface surface is positioned a radial distance beyond the central longitudinal axis, the root radial distance defining an inner radius of the groove, and the interface surface is positioned at the top of the interface surface beyond the central longitudinal axis at an outer top radial distance, the top radial distance is greater than the bottom radial distance; wherein at least one of the installation transmission surfaces and the disassembly transmission surfaces is configured to define a spiral, the spiral has a structure with the center The longitudinal axis is spaced apart from a starting point by a starting radius, and the spiral extends to an outer terminal point with a radius not exceeding about 3.5 times the starting radius. The screwdriver of claim 76, wherein the groove has exactly four or six of the wings. A threaded fastener including: a male-configured fastener having a head, a threaded shank defining a central longitudinal axis, and a male portion formed with a thread extending axially outwardly from the head A protrusion, the protrusion includes a central portion and a plurality of leaves radiating outward from the central portion, wherein: each of the leaves has an installation transmission surface and a disassembly transmission surface, and the installation transmission surface and the disassembly transmission surface The transmission surfaces are constructed to be aligned parallel to the central longitudinal axis; the mounting and dismounting transmission surfaces of adjacent lobes are separated by a transition profile forming the radially innermost portion of the lobes; a wedge shape forming A tapered interface surface is present in the transition profile. The interface surface has a top, a bottom and a pair of opposing edges. The interface surface has a width from close to a top of the protrusion to at the top of the interface surface. The wider part gradually tapers to the a narrower point at the base of the interface surface proximate a base of the protrusion; and the interface surface is located at the base of the interface surface a root radial distance beyond the central longitudinal axis, the root radial distance Defining an inner radius, the interface surface is positioned at a top radial distance beyond the central longitudinal axis at the top of the interface surface, the top radial distance being greater than the bottom radial distance; wherein the installation transmission surfaces and the disassembly At least one of the transmission surfaces is configured to define a spiral having a starting point spaced a starting radius from the central longitudinal axis, and the spiral extends to a radius not exceeding approximately 3.5 times the starting radius. An external terminal point. The threaded fastener of claim 78, wherein the protrusion has exactly six or four of the lobes.